Water is one of the most abundant resources on earth. It makes up more than 2 thirds of Earth. The physics of water is extremely important as it affects our biological wellbeing, but also it helps to regulate the climate. Water constantly moves between its 3 physical conditions: LIQUID, SOLID, and GAS. The cycle of water is called the hydrologic cycle. This cycle is like a recycling process and it makes sure to reuse the water. This cycle involves the transfer of water from underground resources to rivers and biological creatures and plants. After the water has been used by living beings, It is usually returned to the ground or it is evaporated, which is what plants do. Then this vapor is converted to rain and it precipitates to the oceans and the ground, thus starting the cycle all over again.
To understand water and its uses, we need to understand its physical properties. First off, water is a massive reservoir of heat. It is a great way for nature to absorb the energy of the sun without dispersing. During the day, oceans heat up slowly and during the night they cool slowly. This creates a cushion for marine life to survive, as this way they do not suffer extreme temperature changes. This process is equally the same in lakes, bays, and rivers. During the winter, water has a property that helps life to survive. That is the partial freezing of water, which means that only the surface of the ocean, lakes, and other water bodies freeze and not the whole. This creates a cushion from harsh atmospheric conditions and allows for the life underneath the ice cushion to survive.
These are the properties of water that is standing. Then we have water that is moving. The first example is rivers. Rivers with their flow change the landscape and carve the earth. I mean, hey look at the Great Canyon. It is the work of millions of years of corrosive water flow.
Flowing water can have more immediate effects. The flow of water is affected by the wind and the ground beneath it. When there are strong winds, they empower the flow of water. Such are tides. It is important to note that tides are also affected by the gravitational pull of the Moon, but strong winds can create dangerous tides.
When the ground that water is flowing changes, then water gets some dangerous properties. Such is the case of tsunamis. When there are underground earthquakes that are located in the ocean, then the ground moves and all that energy is transferred to the water, which raises in level. This change in level creates tsunamis which have large tides and become dangerous.
To control water, we have multiple physical structures. Dams serve to block the flow of water and to contain it within an enclosed space. If this enclosed body of water is left to flow from an altitude, then water carries what is called potential energy, which is the energy that an object has due to altitude. The energy that water has from being left to flow from an elevated level to a low level, is then transferred to electrical energy thanks to hydroelectric engines.
Bridges, on the other hand, offer the opportunity to cross the barriers created by the flow of the water. Boats use the very properties of water to stay afloat. The actual physical law is called the Archimedes principle.